Quickest way to extract *some* oil from a compressor that's not being replaced?

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I don't know if this is widely accepted, but it's what I'm going with: The gentleman that put this class on states that we need only a 20% POE charge to get adequate oil return in a typical (non-lengthy non-crazy piping) high temp application. (That specific point isn't in the slide show.) The many experienced medium and low temp dudes in attendance did not object. One manufacturer's experiments showed 10% as being sufficient. 20% will be my minimum, generally more.

That being the case, there's no need to cut both lines and tip the compressor to get all the mineral oil out. When possible I'll leave the compressor in place, cut the suction line only and suck some oil out before putting the POE in.

I just wanted to know if anyone has done that or something else. I don't know how easily a plastic tube will fit down inside and if it will catch on something. I may have to yank the compressor.

I've performed a lot of searches on this forum and on the net in general. It appears that, for high temp at least, R-438A is the best no oil change choice and R-407C is the best "some oil change choice".

Thank you Sic! The point of this thread is to, if possible, avoid compressor removal. Maybe it's a crazy thought, but I won't know till I try.

I have and use a small engine oil remover like the ones linked to do oil changes on 12.5 ton and larger scrolls in tandem setups that do not have an oil drain. But I have only ever used the oil equalization/site glass port. I'm just not sure if pulling out the suction will allow access to most of the oil.

I have done this once on a L'unite/Tecumseh R22 comp, it was a rotalock model so no pipe to feed tube along. You will need something super flexible, i used silicone fuel tube for radio controlled cars.
The compressor was a replacement for a failed model that had pumped its oil out on failure, it was in a roof space with limited room to remove it and tip it up which would have been a better option. (ended up taking out three times the correct oil)

Personally if there is room i would remove the compressor and carefully measure out all the oil and replace with poe. Mixes of different oils can go frothy and lead to lubrication failures, depends on what additives etc there is in the oil. Not worth the risk imho.
When i did a lot of work with Castrol when they were developing their Icematic poe oils they recommended the residual mineral content be below 3% which generally took 3 to 4 complete changes and some run time.

You will not be able to feed a pipe down inside a copeland scroll as the stator is quite tight to the shell. Some of the bigger ones have strainers in the inlet anyway.

I have done this once on a L'unite/Tecumseh R22 comp, it was a rotalock model so no pipe to feed tube along. You will need something super flexible, i used silicone fuel tube for radio controlled cars.
The compressor was a replacement for a failed model that had pumped its oil out on failure, it was in a roof space with limited room to remove it and tip it up which would have been a better option. (ended up taking out three times the correct oil)

Personally if there is room i would remove the compressor and carefully measure out all the oil and replace with poe. Mixes of different oils can go frothy and lead to lubrication failures, depends on what additives etc there is in the oil. Not worth the risk imho.
When i did a lot of work with Castrol when they were developing their Icematic poe oils they recommended the residual mineral content be below 3% which generally took 3 to 4 complete changes and some run time.

You will not be able to feed a pipe down inside a copeland scroll as the stator is quite tight to the shell. Some of the bigger ones have strainers in the inlet anyway.

when you say '3-4 change's , you mean you dumped and refilled 3 times the poe oil? I maybe posting here soon of experiment with r-407c. We plan to pick one unit in class and retrofit 407 on it and see how it performs.